Contour Integration and Branch CutsYeah, I need to look into it. There are just many integrals of the same type in this field and all of them gives hypergeometric functions (this can we shown to be the correct solution by other independent methods). I think the conclusion is that I'm misunderstanding some details in what these papers do. I am now pretty convinced that the way I understood the integrals to begin with, cannot be correct. Thanks for your nice answer, it has been very helpful.